Index: build/test/test.tcl
==================================================================
--- build/test/test.tcl
+++ build/test/test.tcl
@@ -134,12 +134,12 @@
 		return false
 	}
 
 	set addrCheck [::nano::address::fromPublicKey $pub]
 	if {$addrCheck ne $addr} {
-		puts "\[1.FAIL\] Got: $addrCheck"
-		puts "\[1.FAIL\] Exp: $addr"
+		puts "\[2.FAIL\] Got: $addrCheck"
+		puts "\[2.FAIL\] Exp: $addr"
 
 		return false
 	}
 
 	return true
@@ -148,27 +148,64 @@
 proc test_blocks {} {
 	set seed [binary decode hex C4D214F19E706E9C7487CEF00DE8059200C32414F0ED82E5E33B523AEDF719BA]
 	set key [::nano::key::computeKey $seed 0 -hex]
 	set address [::nano::address::fromPrivateKey $key -xrb]
 
+	# High-level primitives
+	## Receive/Open
 	set block [::nano::block::create::receive \
 		to $address \
 		amount 1000000000000000000000000000000 \
-		sourceBlock 207D3043D77B84E892AD4949D147386DE4C2FE4B2C8DC13F9469BC4A764681A7 \
+		sourceBlock "207D3043D77B84E892AD4949D147386DE4C2FE4B2C8DC13F9469BC4A764681A7" \
 		signKey $key
 	]
 
+	set blockDict [::json::json2dict $block]
+	set blockSignature [string toupper [dict get $blockDict signature]]
+	set blockSignature_expected "B574DE37F5FFF3DCFB5D0E505FC36B402444777CAA99BA86F89E9B82B6EB901B809554287F0B67D8C2A8306B4F69FE77FD0C9B3D0D10422A02CFEBB3810C7D02"
+	if {$blockSignature ne $blockSignature_expected} {
+		puts "\[1.FAIL\] Got: $blockSignature"
+		puts "\[1.FAIL\] Exp: $blockSignature_expected"
+
+		return false
+	}
+
+	## Send
 	set block [::nano::block::create::send \
 		from $address \
 		to "xrb_1unc5hriitrdjq5dnyhr3zmd8t5hm7rhm9a1u3uun5ycbaacpu649yh5c4b5" \
 		previous "D46BFC2E35B5A3CA4230839D67676F4A8498C2567F571D2B66A7F7B72214DEEE" \
 		previousBalance 1000000000000000000000000000000 \
 		amount 1000000000000000000000000000000 \
 		signKey $key
 	]
 
-	set block [::nano::block::toDict [::nano::block::fromJSON $block]]
+	set blockDict [::json::json2dict $block]
+	set blockSignature [string toupper [dict get $blockDict signature]]
+	set blockSignature_expected "BFE238A27FFBFBCF722EDC3700CA8E2405F5AE18E353E591917A2CBE393F0759C948E710DD723B3BFB21B491D9D0856EEFCAC0E25C7E5FF06185FE5D633B5204"
+	if {$blockSignature ne $blockSignature_expected} {
+		puts "\[2.FAIL\] Got: $blockSignature"
+		puts "\[2.FAIL\] Exp: $blockSignature_expected"
+
+		return false
+	}
+
+	# JSON Parsing a block
+	set blockDict [::nano::block::toDict [::nano::block::fromJSON $block]]
+	dict unset blockDict _blockData
+	dict set blockDict signKey $key
+
+	set block     [::nano::block::jsonFromDict $blockDict]
+	set blockDict [::json::json2dict $block]
+	set blockSignature [string toupper [dict get $blockDict signature]]
+	if {$blockSignature ne $blockSignature_expected} {
+		puts "\[3.FAIL\] Got: $blockSignature"
+		puts "\[3.FAIL\] Exp: $blockSignature_expected"
+
+		return false
+	}
+
 
 	return true
 }
 
 set tests {

Index: nano.tcl
==================================================================
--- nano.tcl
+++ nano.tcl
@@ -256,27 +256,76 @@
 		}
 	}
 
 	return $blockData
 }
+
+proc ::nano::block::signBlockHash {blockHash key args} {
+	set outputFormat "bytes"
+	foreach arg $args {
+		switch -exact -- $arg {
+			"-hex" {
+				set outputFormat "hex"
+			}
+			"-binary" {
+				set outputFormat "bytes"
+			}
+		}
+	}
+
+	if {[string length $blockHash] != 32} {
+		set blockHash [binary decode hex $blockHash]
+	}
+
+	if {[string length $key] != 32} {
+		set key [binary decode hex $key]
+	}
+
+	set signature [::nano::internal::signDetached $blockHash $key]
+
+	if {$outputFormat eq "hex"} {
+		set signature [string toupper [binary encode hex $signature]]
+	}
+
+	return $signature
+}
+
+proc ::nano::block::signBlock {blockData args} {
+	set blockHash [::nano::block::hash $blockData]
+
+	tailcall ::nano::block::signBlockHash $blockHash {*}$args
+}
+
+proc ::nano::block::verifyBlockHash {blockHash signature pubKey} {
+	if {[string length $blockHash] != 32} {
+		set blockHash [binary decode hex $blockHash]
+	}
+
+	if {[string length $pubKey] != 32} {
+		set key [binary decode hex $pubKey]
+	}
+
+	set valid [::nano::internal::verifyDetached $blockHash $signature $pubKey]
+
+	return $signature
+}
+
+proc ::nano::block::verifyBlock {blockData args} {
+	set blockHash [::nano::block::hash $blockData]
+
+	tailcall ::nano::block::verifyBlockHash $blockHash {*}$args
+}
 
 proc ::nano::block::_dictToJSON {blockDict} {
 	array set block $blockDict
 
 	if {[info exists block(signKey)] && ([info exists block(_blockData)] || [info exists block(_blockHash)])} {
 		if {![info exists block(_blockHash)]} {
 			set block(_blockHash) [binary encode hex [::nano::block::hash $block(_blockData)]]
 		}
 
-		set signKey   [binary decode hex $block(signKey)]
-		set blockHash [binary decode hex $block(_blockHash)]
-
-		set signature [::nano::internal::signDetached $blockHash $signKey]
-		set signature [binary encode hex $signature]
-		set signature [string toupper $signature]
-
-		set block(signature) $signature
+		set block(signature) [::nano::block::signBlockHash $block(_blockHash) $block(signKey) -hex]
 	}
 
 	if {$block(type) eq "state"} {
 		if {![info exists block(link)]} {
 			set block(link) [::nano::address::toPublicKey $block(link_as_account) -hex]